R&D Parts upgrade
R&D does not upgrade parts to the new versions. Switching from 1.3.1 to 1.6.
Opened a craft from version 1.3.1. Notified Stack Separator TR18D not available. Attempted to upgrade to new skins? Entered R&D.
Attempting to upgrade all parts.
Purchased the parts in R&D (Right to Left/newest to oldest).
The part is not available in VAB.
Repeat a few times.
Parts are duplicated in R&D.
Switching back to 1.3.1